The Nucleus and Ribosomes Eukaryotic vs Prokaryotic Cells

The Nucleus and Ribosomes

Eukaryotic vs. Prokaryotic Cells Similarities to Prokaryotes Plasma membrane Cytoplasm (cytosol) Ribosomes.

Eukaryotic vs. Prokaryotic Cells Larger Membrane-bounded “true” nucleus Structurally more complex organelles cytoskeleton. Belong to domain eukarya Kingdoms fungi, animalia, plantae, and protista

Structure of the Nucleus Diameter of about five micrometers ( m). Chromatin Contains DNA, protein, and some RNA. Threadlike Coils into chromosomes DNA and determines characteristics of the cell by coding for rotein.

The Nucleus Chromosomes rodlike formed during cell division coiled or folded chromatin.

The Nucleus Nucleoplasm semifluid medium of nucleus.

The Nucleus Nucleoli dark-stained spherical bodies in nucleus where r. RNA and proteins join to form ribosomes.

The Nuclear Envelope double membrane separates nucleoplasm from cytoplasm.

Nuclear Pores (100 nm) protein ribosomal subunits

Ribosomes Cooridinate assembly of amino acids into polypeptide chains (i. e. protein synthesis).

Ribosomes attached to ER depend on an ER signal sequence to bind to a receptor protein.

Ribosomes Eukaryotic slightly larger than prokaryotic Composed of a large and a small subunit. Each subunit has its own mix of protein and r. RNA.

Ribosomes

Polyribosomes Several ribosomes synthesizing Same protein; may be attached to or may lie free.